The present invention concerns a method of operating an internal combustion engine-reformer installation having the features of a classifying portion, and such an internal combustion engine-reformer installation having the features of a classifying portion.
In the operation of an internal combustion engine—in particular a gas engine—it may be advantageous for at least a part of the fuel to be reformed into a synthesis gas prior to combustion. That means that endothermic and exothermic reactions take place in a so-called reformer, in which a hydrogen-bearing synthesis gas is obtained from the fuel. The addition of that hydrogen-bearing gas to the combustion mixture makes it possible, for example, to improve the ignition characteristics or to reduce the production of unwanted emissions.
Installations in which both an internal combustion engine and also a reformer are integrated are known in the state of the art, such as the installation in U.S. Pat. No. 6,508,209 B1.
Admittedly, the regulation of a reformer on the basis of a predetermined ratio of steam to carbon or oxygen to carbon is known. It will be noted, however, that these regulation concepts are designed for a production of synthesis gas, that is as constant as possible. They cannot satisfy the varying needs for synthesis gas of an internal combustion engine. A simple solution to that problem would be to maintain a buffer volume of synthesis gas or to produce synthesis gas to a relatively high extent and burn off the excess. Those solutions, however, are not appropriate in energy terms and considerably reduce the efficiency of the installation.
A concept for regulating an internal combustion engine-reformer installation was disclosed in US 2004/0050345 A1. In that case, the desired amount of fuel which is fed to the reformer is determined on the basis of the injection amount of the internal combustion engine.
A disadvantage in that respect is that upon a change in the operating point of the internal combustion engine, the amount of synthesis gas provided is not that which is required at the time but that which corresponds to the operating point prior to the change. In the case of changes in load which in practice occur frequently, the result of this is that significantly too much or too little synthesis gas is delivered to the internal combustion engine.